Which factor is irrelevant for the opening of stomates?

Question

Quizplus · Accepted Answer

Three other factors,aside from water availability,regulate whether stomata open or close.(1)The presence of light causes stomata to open.Evidence suggests that the absorption of blue light by a flavin protein sets in motion the cytoplasmic response that leads to opening of stomata.(2)A high concentration of carbon dioxide causes stomata to close.Perhaps there is a receptor in the plasma membrane of guard cells that brings about inactivation of a H+ pump when carbon dioxide concentration rises,as might happen when photosynthesis ceases.(3)Abscisic acid (ABA),produced by cells in wilting leaves,can cause stomata to close.Like carbon dioxide,ABA most likely promotes the inhibition of a H+ pump and,in that way,hinders the creation of conditions that cause water to enter guard cells by osmosis.

Which Factor Is Irrelevant for the Opening of Stomates